Sir you live in karachi where every kind of stuff is easily avaialble, so this is no excuse. All you have to do is to visit markets like Boltan, Ranchor line area and Saeed manzil etc.
You need to buy a 6 to 8" long metallic tube having around 10mm outer dia that will snug fit inside the air intake duct (take the measurements), a rubber pipe is required to be attached with the tappet cover and then join both these metallic and rubber tube in the centre. Use proper size hose spring clamps at all three points.
Blow from tappet cover at idle indicates that the PCV is sticky and should be replaced with a new part (expert opinion is required here @Hassan1991 @rajaahmed96) and this can be one other reason for low RPM in your case as the engine is designed to have a controlled air leakage to maintain barometric prrssure in the range 240 to 360 mbar at idle (fully warmed up engine under no load conditions).
